Go-karts (known commonly as karts) are generally well-known in the United States. Further, interest in kart racing, in which the karts reach speeds of up to 100 miles per hour around a track, has been increasing in popularity. Generally, karts are rather simple, small, very inexpensive motor vehicles for a single person (the driver), powered by a small two-cycle engine. Karts typically are not street vehicles; they are used generally on special tracks or on other off-road facilities. Racing karts, however, have become quite sophisticated. As an example, the handling characteristics of a racing kart, particularly at high speeds, are quite acute and require a considerable amount of skill and experience. Therefore, anything which interferes with the proper handling of a racing kart is detrimental to its racing performance.
The frame portion of a kart chassis structure is typically conventional in design. It includes two spaced rails on the righthand side of the kart, somewhat greater than 31/2 inches apart. The frame is made from steel tubing which flexes somewhat under stress. Positioned between and secured to the two spaced rails in previous kart designs is a single engine mount to which, in turn, is attached the kart engine, typically by bolts or the like. In a typical kart, including racing karts, the engine is positioned to the side and slightly to the rear of the driver's seat. The engine mount is affixed to the spaced rails and has upright connecting members near the front and the rear of the mount. The upright connections are configured to permit connection of the engine thereto at the front and rear thereof, respectively.
There are significant disadvantages to the above-described engine mount. That engine mount will typically not permit the two rails to flex relative to each other in the vicinity of the mount. In normal kart operation, as indicated above, the chassis flexes somewhat as the kart moves at high speeds around the track. The existing engine mounts prevent that flexing around the point where it is positioned. This results in a "binding" of the chassis during certain aspects of its normal operation, particularly in tight turns, which is, of course undesirable, as it makes handling of the kart more difficult.
In addition, the known engine mount requires an offset configuration in which the engine is positioned not directly over the spaced rails, but offset relative to the spaced rails. This offset is necessary for proper alignment of the chain drive from the engine to the drive wheel sprocket. This offset arrangement of existing single-engine mounts, however, has resulted in a significant breakage problem, particularly around the welds of the mounts.